How this calculator works
The calculator protects an emergency reserve first, then estimates how much of the savings above that reserve and how much of your monthly headroom could be committed to a car. It converts the payment capacity into an indicative financed balance using the APR and term you enter.
The three bands are Budget Wizard planning scenarios, not lender criteria: cautious uses 35% of post-running-cost monthly headroom and 25% of excess savings; balanced uses 55% and 50%; stretch uses 75% and 75%.
How to use it
- Enter monthly take-home pay for context.
- Enter disposable income after normal bills, debt minimums and planned saving, but before the new car.
- Add essential monthly outgoings so the tool can protect your chosen emergency-fund target.
- Add accessible savings and expected monthly car running costs.
- Use a realistic APR and finance term, ideally from a real quote.
Assumptions and limitations
This is a budgeting model, not a lending affordability assessment and not a recommendation to spend up to any band. The risk-band percentages are deliberately transparent planning choices rather than industry rules. Insurance, maintenance, fuel and resale values vary widely. A longer finance term can increase the purchase price that fits a payment while also keeping you in debt for longer.